Fireproofing compound.



IVILLIAM D. PATTEN, OF NEWV YORK, N. Y.

FIREPROOFING COMPOUND.

Specification of Letters Patent.

Patented Oct. 1'7, 1905.

Application filed June 15, 1904. Serial No. 212,679-

To all whom, it nmy concern:

Be it known that 1, WILLIAM D. PATTEN, a

citizen of the United States, anda resident of the city, county, and State of New York, have 5 invented a certain new and useful Improve- E ment in Fireproofing Compounds, of which the following is a specification.

' My invention relates to fireproofing compounds of that class involving the use of chemicals which fuse at a temperature below the point of wood ignition. thereby inclosing and protecting from flame the fibers of the treated substance. The chemicals possessing this qual- Y ity which have been heretofore generally used volatilize readily at a temperature slightly i above the point of fusion, so that'they are not effective if in the presence of lire for a substantial length of time.

The object'of my invention is to overcome the objection stated and -to produce a fireprooiing compound which, while it will fuse at a temperature below the point of wood ignition. will also maintain its fluidity and not volatilize appreciably in the continued presence of fire.

I have discovered that dihydrogen sodium phosphate, either the pyro salt HzNtlzPzO; or the ortho salt H NaPOi, while it does not of itself fuse below the point of I wood ignition, if treated with a substantial percentage of sulfate of ammonium fuses readily at a temperature below the point of wood ignition, the fused mass being a free fluid and less volatile under fire conditions than any of the compounds heretofore used. "The following experiment shows the relative value of my new fireproofing compound to phosphate of ammonium. Two mixtures were prepared, one containing 66.66 per cent. of phosphate of ammonium and 33.33 per cent-of sulfate of ammonium and the other 66.66 per cent. of dihydrogen sodium ortho phosphate and 33.33 per cent. of sulfate of ammonium. Equal quantities of blotting-paper were saturated with these 'two solutions, respectively, were dried, ignited at a dull red heat for fifteen, thirty, forty-five, and seventy-five minutes,

and weighed. By analysis the non-volatile I residue was determined, and in the following i table the non-volatile residue equals the percentage remaining of the dry salts used:

: -tastes phosphate. phosphate.

i E l i 15 minutes exposure 40 per cent. 63.80 per cent.

i 30 minutes exposure 16.30 per cent. l 59.50 per cent.

i minutes exposure 5 per cent 59.20 per cent. 75 minutes exposure g 4,50 per cent. 1 58 per cent.

, In the practical application of my invention I substitute for each part of phosphate of ammonium as now used a mixture comprising two-thirds parts of dihydrogen sodium ortho phosphate and one-third part of sulfate of ammonium. For instance, if the solution phosphate of ammonium and sulfate of ammonium in the proportion of one pound of phosphate of ammonium to two pounds of sulfate of ammonium I would substitute for the one pound of phosphate of ammonium a mixture comprising two-thirds of a pound of dihydrogen sodium ortho phosphate and onethird of a pound of sulfate of ammonium, the substitution of the two-thirds parts of dihydrogen sodium ortho phosphate and the onethird part of the sulfate of ammonium for the one part of phosphate of ammonium being'in addition to the two parts of sulfate of ammonium originally in the twenty-per-cent. mixture.

My experiments show that the explanation of the valuable results occurring from'the use of dihydrogen sodium phosphate, asdescribed, is, that the sulfate of ammonium reacts on the dihydrogen sodium phosphate, freeing ammonia-gas and leaving either a mixture or an undetermined chemical combination of meta or pyro phosphate of soda and meta or pyro phosphoric acid together with sulfate of soda dissolved therein, which said mixture has the properties stated of free fluidity in a state of fusion at a temperature below the point of wood ignition, but does not readily volatilize. The essential for reaching the result is that part or all of the sodium base should be ex tracted from the dihydrogen sodium phosphate by any suitable chemical under the action of heat at a temperature below the ignition-point of wood, as illustrated by the following formula, (N :nO-XNmO) P2O5,the value contained a twenty-per-cent. mixture of of X being one or less, but if less than one still of sufiicient value so that the resultant mixture or chemical combination of meta or pyro phosphate oi soda and meta of pyro phosphoric acid shall fuse and be freely fluid at a temperature below the ignition-point of wood.

I have discovered by experimentation that sulfate of ammonium in combination with di: hydrogen sodium phosphate, as hereinbefore described, is most effective and desirable; but the similar use of any other chemical having an equivalent action on dihydrogen sodium phosphate and which as a result of the extraction from the combination of part of the sodium base produces a salt which under the conditions described will he possessed of free fluidity at a temperature below the ignition-point of wood and not readily volatilizable would be within the scope of my inven: tion.

I do not desire to restrict myself to the use of the precise chemicals or proportions hereinbefore stated; but

hydrogen sodium phosphate and sulfate of ammonium in such proportions that the resulting compound is freely fluid at a temperature below the point of wood ignition.

4. A fireproofing compound containing dihydrogen sodium ortho phosphate and sulfate of ammonium in such proportions that the resulting compound is freely fluid at a temperature below the point of wood ignition.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

WILLIAM D. PATTEN. VVi'tnesses:

JOHN S. HOWELL, SEABURY C. MAs'rIcK. 

